Well seals



March 31, 1970 CAHEATWOOD ET AL 3,503,635

WELL SEALS Filed Aug. 28, 1968 M m i I 42 M l 5@ 54 @2 I 40 L 1 Z4-+ (:2 44- 8 I 4'8 1'7 w i @0 5e 224 I 140 Mb l his I l l TIES United States Patent 3,503,635 WELL SEALS Lowell K. Cheatwood, Oklahoma City, and Jess A. Poindexter, Bethany, Okla., assignors to Jess and Lowell Well Casing Company, Oklahoma City, Okla., a corporation of Oklahoma Filed Aug. 28, 1968, Ser. No. 755,850 Int. Cl. F16] 21/04 U.S. Cl. 285138 Claims ABSTRACT OF THE DISCLOSURE A device for forming a double sanitary well seal on well casing, the device consisting of a cover cap including an annular flange which is placeable over and around the top opening of a well casing, and including a gasket and insert plate disposed down within the top opening of the well casig such that the insert plate can be drawn toward the cover cap to displace the gasket radially outward into firm, sealing engagement with the inside of the well casing to further expand the casing outward for double sealing against the cover cap annular flange.

BACKGROUND OF THE INVENTION Field of the invention The invention relates generally to well head seals and, more particularly, but not by way of limitation, it relates to improved well seals formed from plastic for use with various forms of water well casing.

Description of the prior art The prior art includes varied types of well seal devices which are inserable downward within a well casing such that application of tension can bring about expansion of a gasket material to form a seal. Such prior art devices are formed from cast iron or other metallic substances and provide only an insertion-type cap with no possibility of effecting a second outer seal and easing reinforcement around the outer wall of the well casing. The advent of extruded plastic well casing for usage in such as water wells and other shallow applications has brought about certain problems in utilization; the prior-type well seals were often found to split the casing wall thereby to loose sealing effectiveness when any slightly excessive sealing pressure was applied and such criticality can contribute to needles attention and time loss on the job.

SUMMARY OF THE INVENTION The present invention contemplates a well seal which is formed from plastic material to provide a double sealing contact. In a more limited aspect, the invention consists of an outer cover means having an end plate including an annular flange, having a gasket, an insert plate, and a plurality of fasteners or securing means for drawing the insert plate toward the cover plate while the gasket means is squeezed therebetween and expanded along radial axes. Thus, the cover end plate can be inserted over a well casing with the annular flange fitting therearound while the gasket and the insert plate are inserted and adjusted to provide optimum pressure of the gasket against the inner walls of the well casing to expand the well easing into sealing contact with the annular flange of the cover means.

Therefore, it is an object of the present invention to provide a well seal which is formed from a material having a desirable degree of resilience.

It is also an object of the invention to provide a double sealing well seal capable of providing a sealing contact with the inner wall of a well casing and any conduit pipes 3,503,635 Patented Mar. 31, 1970 BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an exploded perspective view of the various well seal components relative to a section of well casing;

FIG. 2 is a vertical section of a well seal constructed in accordance with the present invention as installed atop a well casing; and

FIG. 3 is a perspective view of an alternative form of well seal as constructed in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION As shown in FIG. 1, a well seal 10 is intended for double sealing disposition about an upper edge 12 of a well casing 14. The well casing 14 may be either the conventional cast iron casing pipe or it may be one of the more recently developed types which are extruded from the class of plastics including styrene, polyvinylchloride, acrylonitrile butadiene styrene, and other polymers having similar properties.

The sealing components of well seal 10 are also formed of a selected plastic having a suitable resiliency, which property enables its double scaling function while providing reinforcement to prevent longitudinal cracking of the casing 14 during installation as will be further described. In one form, the sealing components of well seal 10, an end cap 16, and an insert plate 17 are formed from a rubber modified styrene, a mixture of about 12% butyl rubber and polystyrene. This material imparts a desired resiliency to end cap 16 and insert plate 17 such that they achieve a unique double seal when installed. A gasket 18, to be further described, is disposed between end cap 16 and insert plate 17.

Referring also to FIG. 2, the end cap 16 consists of an end plate 20, shown as being round in shape but which actually may take any configuration which conforms to the cross-section of a well casing 14 or such. A collar flange 22 is then bonded about the outer perimeter of end plate 20 such that it will extend over the end 12 of an adjoining section of well casing 14. The collar flange 22 may be integrally formed with the end plate 20 by conventional molding or milling methods, or it may be formed by bonding a collar portion 22 to a separate end plate 20 by means of conventional bonding techniques as by using methyl-ethyl ketone or other suitable solvent bonding agents.

The end plate 20 is formed to have a plurality of holes disposed therethrough. Thus, it includes a plurality of equi-spaced fastener holes 24 as well as a central hole 26 which receives a liquid recovery conduit 28 therethrough in close-fitting relationship. In the case of well seal 10, it contains a single conduit hole 26 as it is adapted for use with well-known forms of submersible pump which may be installed down the well casing 14. Also then, a cable hole 30 having a threaded counterbore portion 32 is formed to allow passage of an electrical cable for supplying drive energy to the submersible pump. The cable hole 30 is sealingly closed by means of a suitable packing or resilient O-ring 34 as retained by a feedthrough plug 36. Still an additional access hole 38 having a threaded counterbore portion 40 and being sealingly closed off by a plug 42 provides access into the interior of well casing 14 for whatever reasons that may arlse.

The gasket 18 may be formed from a suitable resilient material such as rubber or one of the softer plastics which is suitable for gasket use. Gasket 18 is formed to have a hole pattern therein which is similar to the hole pattern in end plate 20. Thus, gasket 18 has a plurality of fastener holes 44 as well as a central conduit hole 46, with a cable hole 48 disposed on one side and an access hole 50 disposed on the other side thereof. The gasket 18 is shaped similarly to end cap 20 but it is formed to have a slightly smaller diameter or cross-sectional configuration so that it can fit down within an upper end 12 of well casing 14.

The insert plate 17 is formed to be of the same size and having the same hole pattern as gasket 18. Thus, insert plate 17 includes fastener holes 52, conduit hole 54, cable hole 56 and an access hole 58. A plurality of fasteners such as bolts 60, washers 62 and nuts 64 are secured through the respective end fastener holes 24, gasket fastener holes 44 and insert plate fastener holes 52. The tightening of the fasteners, or nuts 64 on bolts 60, results in a squeezing of gasket 18 to force the gasket material to expand radially in the horizontal plane such that sealing connection can be effected by whatever the desired amount.

In operation, the well seal is initially assembled with insert plate 17 and gasket 18 held loosely against the underside of end plate 20 by means of fastener bolts 60 and loosely threaded nuts 64. This assembly places Well seal .10 in its assembly condition with no fiexure applied to gasket 18 such that well seal 10 can be placed over the well casing 14. The well seal 10 can thus be placed over the upper end 12 of well casing 14 with collar flange 22 in loosely contacting disposition adjacent or around the outer wall 14a of casing 14, and with insert plate 17 and gasket 18 inserted within and loosely contacting the inner casing wall 1411, as shown in FIG. 2.

When the well seal 10 is properly placed over Well casing .14, the associated electrical cable (not shown) is properly led through cable holes 30, 48 and 56, and the feed-through plug 36, is tightened to form a sealing collar thereabout. Also, the liquid recovery conduit 28 is properly positioned through the respective conduit holes 26, 46 and 54 of end plate 20, gasket 18 and insert plate 17, respectively.

Applying an even tightening to fastener nuts 64 will tend to squeeze the more resilient material of gasket 18 such that a plurality of sealing pressures are applied. First, the gasket 18 is forced outward about its perimeter to effect a tight, sealing contact about the inner wall 14b of casing 14. Second, the gasket 18 is expanded about each of the holes therethrough such that it effects a tight sealing contact thereabout; that is, a seal with strength proportional to fastener tension is effected about the electrical cable in cable hole 48 as well as about the recovery conduit in conduit hole 46, and around each fastener in the various fastener holes 44. In addition, a third seal is effected by virtue of the fact that the upper end 12 of well casing 14 is easily distended outward in its radial direction upon expansion of the well seal 10; this is even true to a lesser extent with metallic types of well casing. That is, additional sealing effect is realized between the casing outer wall 14a and the inner wall 22a of collar flange 22. Also, while sealing is effected between inner wall 22a and easing outer wall 14a, the collar flange 22 also supplies a reinforcement to prevent splitting of the casing 14 longitudinally as occurs when an excessive expansive force is applied using prior types of seals. This outer sealing and reinforcement feature of collar flange 22 is also effective when the well seal 10 is employed with the cast iron types of casing 14 since they too are subject to some degree of radial expansion during the sealing affixure.

FIG. 3 depicts a modified form of well seal 70 which functions in the same manner as well seal 10 but which is adapted for use with the conventional, surface-mounted jet pumps which supply a pressure input along a conduit 72 with liquid recovery being effected through conduit 74. Thus, the construction of well seal 70 is very nearly the same as well seal 10 except that an end plate 20a of end cap 16 includes two oppositely disposed conduit holes 76 and 78 for receiving respective conduits 72 and 74. The respective gasket and insert plate (not shown) would be formed in similar configuration. The jet-type pump also results in elimination of the cable holes since no electrical energy is needed down the well and an access hole such as shown in FIG. 2 (aligned holes 38, 50 and 58) may or may not be supplied in accordance with preference or particular usage.

The foregoing sets forth a novel well seal assemby which is adaptted for use with either cast iron well casing or extruded plastic casing, and which assembly enables a unique double sealing effect. The well seal assembly is constructed through very economical forming methods from relatively low cost plastic material such that it imparts qualities of high strength and increased sealing capability to the art without sacrificing other factors such as weather-resistance, sanitary attributes, and generally expected long service life.

Changes may be made in the combination and arrangement of elements as heretofore set forth in the specification and shown in the drawing; it being understood that changes may be made in the embodiments disclosed without departing from the spirit and scope of the invention.

What is claimed is:

1. A double sealing cap device for well casing which houses liquid recovery conduit within its inner wall, comprising:

a well casing;

covermeans including an end plate shaped similar to the cross-sectional configuration of said casing and an annular flange formed around the perimeter of said'end plate extending along the outer wall of said casing, said annular flange being long enough to envelope a substantial length of said casing adjacent the end plate, said end plate including a opening for receiving a conduit therethrough;

insert plate means having a shape similar to said end plate disposed within said casing, said insert plate means including an opening for receiving a conduit therethrough;

gasket means formed of resilient material and having a shape similar to said insert plate means disposed within said casing between said cover means end plate and insert plate means, said gasket means including an opening for receiving a conduit therethrough, said annular flange extending axially beyond said gasket; and

securing means fastening said insert plate means to said cover means end plate through increasing tension such that said resilient gasket means is displaced to form a seal around a conduit, and is displaced radially outward to form a seal around the inner wall of said casing and radially outwardly deforming the outer wall of said casing into sealing engagement with said annular flange.

2. A double sealing cap device as set forth in claim 1 which is further characterized in that: said cover means end plate, insert plate means and gasket means each include a second opening for receiving a second conduit therethrough.

3. A double sealing cap device as set forth in claim 1 which is further characterized in that: said cover means end plate, insert plate means and gasket means each include an additional hole which holes align each with the other to receive an electrical cable therethrough.

4. A double sealing cap device as set forth in claim 2 which is further characterized in that: said cover means, insert plate means and gasket means each include an additional hole which holes align each with the other to receive an electrical cable therethrough.

5. A double sealing cap device as set forth in claim 1 which is further characterized in that: said cover means, insert plate means and gasket means each have an additional hole extending therethrough in alignment each with the other to provide access to the interior of the well casing.

6. A double sealing cap device as set forth in claim 1 wherein said securing means comprises: a plurality of bolts equally spaced to extend through said cover means, insert plate means and gasket means, and each being secured under variable tension by respective nuts threaded thereon.

7. A double sealing cap device as set forth in claim 1 which is further characterized in that: said cover means, including the end plate and the annular flange, and said insert plate means are each formed from a rubber modified plastic polymer.

8. A double sealing cap device as set forth in claim 7 which is further characterized in that: said rubber modified plastic polymer is polystyrene modified with approximately twelve percent butyl rubber to impart a predetermined degree of resiliency to the cover means and insert plate means References Cited UNITED STATES PATENTS 2,237,680 4/1941 Mark 285-346 X 2,735,697 2/1956 Zanin 285338 X 2,800,242 7/1957 Sauthoff 285139 X 2,954,742 10/1960 Williams 285139 X 2,956,822 10/1960 Kates 285139 X 3,082,022 3/1963 Moore 285423 X 3,254,153 5/1966 Kohler 285137 X DAVID J. WILIAMOWSKY, Primary Examiner DAVE W. AROLA, Assistant Examiner US. Cl. X.R, 

